Db2 for z/OS Utilities in Practice

Reorganizing Db2 data

REORG is a utility for the maintenance of application data and indexes. There are a number of reasons for running this utility, but some of the most common include keeping data organized for application performance, applying changes to the table space schema, formatting data rows, or redistributing and discarding of data rows. These functions are all expected to be done with little disruption of application availability. Here’s a more detailed list:

•Materialization of schema changes:

 – Adding columns

 – Altering column data ...